Field of the Invention
The present invention relates to a sensor for measuring shear force and a dummy for testing a vehicle using the same. More particularly, it relates to a sensor for measuring shear force which is configured to quantitatively accurately measure shear force applied to a human body who sits on a vehicle seat, and a dummy for measuring shear force using the sensor.
Description of Related Art
Seats for vehicles are typically designed to have a structure configured to primarily protect an occupant from vibrations or shocks in light of characteristic values of the human body, and are manufactured to have a structure capable of providing riding comfort.
Particularly, depending on the structure of the seat for vehicles, muscle fatigue of the occupant and the load applied to the lumbar of the occupant vary. Therefore, to accomplish a high level of comfort while riding in the seat, when the seat is designed, the muscle fatigue and the load applied to the lumbar of the occupant should be sufficiently considered.
Therefore, to development the seat, a process of measuring the pressure distribution on the occupant who sits on the seat is required.
In the present regard, the process of measuring the pressure distribution on the occupant includes determining the vertical load caused by the vertebral body of the occupant. Furthermore, since the riding comfort of the seat is affected not only by the vertical load of the occupant but also by shear force generated when the occupant is on the seat, it is preferable that the shear force applied to the occupant as well as the vertical load caused by the occupant be determined.
Given the present case, a shear force measurement apparatus is provided by the present invention. In the present shear force measurement apparatus, a plurality of shear force sensors are disposed in a seat to accurately measure the shear forces applied to respective portions of the seat when an occupant sits on the seat. Thus, taking into account both the vertical load and the horizontal shear force that influence the spine's degree of discomfort or muscle fatigue when an occupant sits on the seat, the shear force measurement apparatus can quantitatively measure the spine's discomfort degree and muscle fatigue.
However, in a conventional shear force measurement sensor, longitudinal and lateral strain gauges are disposed in the horizontal direction. Therefore, the resolution of the strain gauges is limited by the slight variation in the shearing load measured by each gauge.
Furthermore, in the conventional shear force measurement sensor, to minimize the effects of a vertical tensile force on the strain gauge that is horizontally disposed between plates forming the sensor, a separate ball bearing is provided. However, the vertical tensile force still has an effect on the strain gauge, thus reducing the accuracy in measuring the shear force.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.